Figure 2
From: Manipulating Mn–Mgk cation complexes to control the charge- and spin-state of Mn in GaN
Evolution of the Mn spin state.
(a) non-resonant XES for GaN:Mn samples with and without Mg; (b) evolution of the nominal spin value with the ratio between Mg and Mn concentration, extracted from the analysis of XES spectra and calculated via DFT; (c) computed spin polarization density [Δρ = ρ(↑) − ρ(↓)] for MnGa in wurtzite (wz)-GaN. The positive and negative spin polarizations are represented by violet and grey colours, respectively; (d–f) difference ρk − ρk–1, between the spin polarizations of the Mn–Mgk complexes, with k = 1, 2 and 3. The red and blue colours represent positive and negative values, respectively. The blue colour in (d) indicates the enhanced delocalization of spin polarization in Mn-Mg, whereas the red colour in (e) and (f) points to a gradual shift of the spin density to Mn in Mn-Mg2 and then in Mn-Mg3. In all plots the contour value is set to 0.005 corresponding to about 2 × 10−5 µBÅ−3.
